Primary Sjogren's syndrome (pSS)-related cerebellar ataxia: a systematic review and meta-analysis

Background Primary Sjogren's syndrome (pSS) is a chronic autoimmune disorder characterized by lymphocytic infiltrates of the exocrine glands, particularly the salivary and lacrimal glands, resulting in oral and ocular dryness. pSS has been linked to various neurological manifestations, including cerebellar dysfunction. We aimed to provide a comprehensive analysis of the currently available evidence regarding pSS-related cerebellar ataxia. Methods A systematic literature search in the PubMed database was performed and 19 papers were eligible to be included in this paper. Results The pooled prevalence of cerebellar ataxia in pSS is estimated to be 1.5% (95% CI 0.3-6.8%). pSS patients with cerebellar involvement have a female-to-male ratio of 6:1. Although most of the patients are adults in their fifth decade of life when diagnosed, cases of children with pSS and cerebellar involvement have been reported. Typical cerebellar ataxia related to pSS manifests with vermian dysfunction, namely gait ataxia and/or cerebellar speech. Cerebellar ataxia due to pSS may also mimic degenerative cerebellar ataxia, especially when the onset is progressive. Conclusions The diagnostic approach to a patient with cerebellar ataxia of unknown etiology should include evaluation for an underlying pSS. A thorough history and clinical examination, antibody testing, brain MRI imaging and/or MRS of the cerebellum will assist in establishing the diagnosis. Setting up a joint neuro-rheumatology clinic can be valuable given that rheumatic and neurological diseases share comorbidities.